Analog output problem

Similar Questions

• Strange problem with analog output PCI 6251 and BNC-2110

  I'm controlling current source of third parties using the connectors of analog output on my card PCI 6251 and BNC-2110.

  The current source needs an input signal of 0.1V. I tested it using a battery, the potentiometer and the voltmeter, and by manually adjusting the voltage of power current works - current output with control voltage scales according to the specifications and is relatively stable.

  The data acquisition card works too - when I connect a voltmeter to the AO0 AO1, the measured voltage corresponds to the target with great precision value.

  But when I connect the current source of third AO0 AO1 data acquisition card, the measured output voltage drops and fluctuates. This applies to both channels of the AO.

  I wonder what is the problem here. I suspect it could be a matter of the grounding - the current analog control of the source is an entry with two floating terminals differential. I tried to return the switches FS/GS on the BNC-2110, but that makes no difference.

  Anyone knows similar behavior? Does anyone have any suggestions?

  
  

• Problem of generation of the analog output on PCI-7342

  I use for the control of servo motor with encoder Axis 1 of my PCI-7342 feedback

  and trying to out of the velocity of the encoder on the analog output of the axis-2 which is currently not used.

  For testing purposes, I pulled out a constant 16383 (half of 32767) to the analog output

  through load DAC.flx permanently, but there is no voltage on the map of the motion.

  I read

  http://digital.NI.com/public.nsf/WebSearch/102BE3EEED8A8B0DC1256EDA0059EC47?OpenDocument

  http://forums.NI.com/T5/motion-control-and-motor-drives/analog-output-voltage-from-UMI-7764/m-p/5219...

  http://forums.NI.com/T5/motion-control-and-motor-drives/configuring-the-analog-output-of-PCI-7358-mo...

  and configure my 2 axis to be a stepper motor. I also tried to disable axis - 2. None of them works for me.

  Also, I tried to read the value of CAD using reading DAC.flx right after that load DAC.flx is called.

  Correctly, the value was shown on the screen. (See the attached figure)

  I'm really bad now. Please, please, please help!

  Any possible solution is fully appreciated!

  Ron Liou

  
  

• To input analog shutdown when the analog output is completed and synchronization

  Hello

  I'm trying to get my LabVIEW program to send analog output to a computer and read acceleration using the cDAQ-9184. Chassis output that I use is the NI 9263 and the chassis of entry is the NI 9234. I generate a signal of white noise using LabVIEW Express signal generator.

  The first problem I have is the synchronization. I had an old VI that has begun to measure the acceleration just about a second after the entry has been given to the machine. I used the LabVIEW tutorial on how to sync the analog input and output, only to discover that it does not work with two different hunts. Then I found another tutorial that shows how to synchronize different frames between them.

  The second problem is the cessation of the LabVIEW program. What I want to do is to generate the signal and then simultaneously send and read the input and output analog, respectively. It is because I don't want a phase difference or any shorter signal for a direct comparison. But as soon as the signal is sent to the machine, I want the entry to stop analog playback and then then the LabVIEW program must stop. I want to be able to choose any length of signal to be generated and stop as soon as the entire duration of the signal has been sent to the machine.

  I tried 'DAQmx stop', "DAQmx Timer" and 'DAQmx's task made?' and none of them have worked for me. It is also my first time on a forum posting, so I hope I gave enough information. I enclose my VI as well. The VI shows I read an entry for the analog input voltage, but I am only using this to try to get to the work programme.

  I'd appreciate any help I could get.

  Thanks in advance

  Peter

  Hi Peter,.

  I have some recommendations for you that I think you will get closer to your solution. First of all, I assumed you meant that you had 1 chassis (cDAQ-9184) who had two modules in it (NOR-9263 and NOR-9234). My next steps are based on this assumption, so if it's wrong, please let me know.

  For your first question about the synchronization, the code you provided is very close to what you need. You need to do, however, implement architecture master/slave for startup tasks DAQmx functions. To do this, you can add another frame to the flat sequence structure and put the master start task (input voltage) after the start slave (output voltage) task.

  To manage your second question and that the program ends at the point where you, the first step is to get rid of all the logic that you use with the local variable of length of time. Rather than use this logic, just wire the node "task performed?" of "is task performed?" operate to stop the loop. This will cause your loop to stop as soon as the signal is sent to the machine.

  I have some other recommendations for you that will increase the performance of your program:

  (1) rather than writing on file inside the last loop, you can use the DAQmx Configure Logging (PDM) .vi. You will place this VI between DAQmx Timing.vi and DAQmx Start Task.vi to the task of the analog input voltage.

  (2) after the last while loop, you want to stop the task and analog outputs as well with another DAQmx stop Task.vi.

  (3) rather than using a local variable for the entrance of displacement and wiring it in the DAQmx Write.vi, you can wire directly from the output waveform of the wave to build function node.

  That should help you get started in the synchronization of these tasks.

  -Alex C.

  Technical sales engineer

  National Instruments

• cFP-AO-200 analog output module (error-33180)!

  Hello everyone

  I use the CFP 1808 Bank as well as other such modules that HAVE 111 and enter I-110, I recently bought a Module AO-200 out of the currents of the order of 4-20 mA, I connected the module to the Bank and updated the device of the MAX Software, then I opened the Getting Started/Analog Output.vi leave examples in Labview to test 2011 map the VI returns an error with the code 33180 for me, I don't know what the problem is, but I tested the card with the MAX and wrote the values to it successfully.

  Can someone tell me what is the problem with my VI

  Thank you

  I was able to reproduce your error. You must select 'All' in the Point IO Point field for this vi.

• How can I check if the counter entry is synchronized with the analog output?

  Hello

  I'm working on an application for counting photons.  I use two channels of analog output on a PCI-6713 card to send a frame model to a set of XY scan mirrors.  I then a photon count unit that emits a TTL signal when the photons are detected as a result of this raster analysis.  I then use a surfboard USB-6211 to count the edges on this TTL signal.

  I have problems that seem due to synchronization problems.  I use the sample AO on the PCI-6713 card clock like the door of my meter on the map USB-6211.  I use a trigger to start digital to analog output and a trigger of arms for the entrance to counter early. Is there a way to check that the analog output and counter entry of start of operations at the same time and are are synchronized?  I basically want to monitor and compare the ao real sample of the PCI-6713 card clock door signal used by the jury of the USB-6211.  I was able to export the sample AO clock and watch it on my oscilloscope, but not the signal from the door of the USB-6211.

  Thanks for your help,

  Brian

  Update... It turns out that there is no problem of synchronization between my meter input and the analogue output.  There was a difference of impedance when I connected my unit of counting photons to my USB-6211.  This caused an error variable count rate.  After accouting for this shift, the problem disappeared.

• How to control the two analog outputs at a time

  I'm new to LabVIEW and have some problems in DAQmx with control outputs analog multiple.

  I want to set up a platform using BNC-2110 and PCIe6363 to control two rotating mirrors. The problem that I can only give an output (AO0 or AO1) at a time and I really have no idea how revise my LabVIEW diagram to control two outputs at the same time I met. I tried to change the outputs and it keeps a mirror turning instead of the old. Could someone help me with my problem and I would really appreciate. This is my blocked diagram and front.

  

  

  Hi zrmaker,

  As mentioned by RavensFan, you should not create 2 analog outputs different tasks if you use AO0 AO1. To your façade > physical control or the channels > select the drop-down list of the control channel physical (s) > Browse > hold down the CTRL + select the AO0 and AO1 > Select OK. Once this is done, you will see that your control or the physical channels has the following input values: "Dev1 / ao0:1" which means that you will access to AO0 AO1.

  In regards to writing DAQmx, simply select Analog > multiple channels > samples multiple > 1 waveform (you should get the following: 1 d Analog Waveform NChan NSamp). Once done, you can just use table build to combine 2 different waveforms and plug in this table to DAQmx writing output. The first index will be the output for AO0 value and the other will be for AO1.

  You can check this link on how to read or write from several channels: http://digital.ni.com/public.nsf/allkb/0C1ADEF06A54AB2D862575040066FD51

  Additional reference:
  http://www.NI.com/white-paper/2835/en/

  Hope that helps.

  Warm greetings,

  Lennard.C

• poor performance analog output (error 200018)

  Hello.  I have a 6124 SMU Board with controller real time SMU-8102.  the Council is speced to MECH 4 analog outputs. / s (one lane), but I have problems to operate at anything beyond about 500 kech. / s.  I enclose my example below program.  If I put the rate at 500 k, it works.  If I put 1 m, it does not work and I get the error 200018 (DAC conversion attempted before Conversion data were available).  I use the DMA transfer.

  I also tried to increase or decrease the number of samples written by loop (between 50 and 300) and using a loop timed in labview real-time.  That essentially gives the same result (sometimes I get error 200016 instead, "exceeding accuracy onboard device memory").

  Because the controller is a dual core controller that do literally anything else (what I showed is the whole program, nothing else running), I don't know that I have some setting wrong software.  I can't believe that this controller is unable to deal with this card.  Does anyone have any suggestions on what I might try?

  Version of LabVIEW is 2010 and DAQmx version is fairly recent.

  Ok. I thought about it.  Here's an interesting fact.  At the rate of 1 MECH. / s, tries to write to 4096 samples each microseconds 4096 works perfectly well.  But any attempt to write to 4095 samples fails!  4095 course is 2 ^ 12-1.  It seems that DMA was running only transfers of 4 k at a time, so when he got 4095 samples, he was waiting for a sample more start the transfer, but at the time where he got this sample, it was too late.  I changed DataXferReqCond property for "almost complete."  Now, I can write about 150 samples at a time instead of 4096.  Greatly improved!

  Moreover, it would be really good to put in the text of the error message for the error 200018 so that others live several days tearing their hair like I did...

  Thanks for the help

  Daniel

• Digital, analog output file trigger

  Hello

  I'm trying to produce an analog output to text file. I have attached the text file with entries and file vi. When I connect oscilloscope, there is no waveform.  I'm using labview for two days. What is wrong with my code?

  Everything is OK now, I had a problem with the clock on board.

• Redeclenchables/continuous to a custom waveform analog output?

  Hello

  I try regular output an analog signal using the box USB-6211 and Labview2009. I looked at various examples of waveform, including the retriggerableAO.vi example, but I can't seem to understand how to send a 'waveform' custom stamp (terminology is perhaps the question). In all the examples (including waveformbuffer), I ran across the single waveform, the options are sine, square, etc.  Previously, I posted on this forum looking for hardware suggestions (link here) and explained what I try to do and got the big help. To sum up, I would like to read a 'waveform' from a text file, send it to the usb-6211 buffer and then continue to an analog channel. At the same time, I'll use the beginning of the analog task to trigger a digital signal once per cycle as well.

  I got in what concerns the establishment of the waveform, but am stuck to figure out how to get into the buffer and setting the frequency, etc.

  Thank you

  Gabe

  Hi Gabe,

  Dennis is correct that it will take some room to modify the existing screws to fit your need.  As he says, the Con Gen tension Wfm - Int Regeneration.vi Clk - no example provided with LabVIEW.  In the example, it can be shown that there is a custom VI used to explain the problems that arise when a waveform of a given frequency to a frequency of sampling and outputs analog specified.

  With all that said, it seems you want to read from an existing waveform file that you created and this waveform to an AO output channel.  There are a few things that will be needed to know before proceeding:

  -What is the waveform as you try to output (5000 samples, 10 k, 100 k, etc.)?

  -What pieces of the size of the wave you want output (100 samples at a time, etc.)?

  -you want to again and again, or simply run through once the waveform looping?

  Assuming that you already have the waveform and will only step by step, here's what I would like:

  -break the large waveform into smaller pieces of waveform of standard size

  -import the waveforms in LabVIEW and create an array of waveforms

  -bring the waveform in the example Dennis mentioned previously with automatic indexing enabled on the tunnel

  -Remove the generator of wave functions existing the while loop

  -wire your indexed table of waveform for the data of the VI DAQmx of analog output terminal

  It is possible that you will have to play with the settings of your waveform and timing of your VI, but this should be a good starting point.  Please let me know if something is not clear or if I have misunderstood your original message.  Have a beautiful reast of the day.

  Best,

• Read analog output channel value internally

  According to this you can read the values of analog output of return without having to physically connect the wires.

  By using the technique described in the example given (DAQmx_Read_Output_Internal_Channels.vi) I'm reading a current area of OCCUPANCY on my compactDAQ cDAQ-9174 with a module of analog output current OR-9265.

  The output channel is created in MAX and my vi can write values to him without problems

  But when I try to create an analog input channel to read the output, an error occurs.

  What I am doing wrong?

  This is not supported by my hardware?

  Or is the example given in the above incorrect link?

  The example is 10 years old. Maybe, it does not work in LV2013.

  

  

  Hi Jocker,

  The link was not attached to your message, but I guess that's it: http://digital.ni.com/public.nsf/allkb/CB86B3B174763C3E86256FFD007A2511 as there the example of vi you mention.

  The error you are getting is due to the use of the channel for analog output and trying to configure the task as a task of entry. You must use _aoX_vs_aognd as the channel of the task rather than on the output channel. This compares to the ground for the analog output values.

  The NI 9265 is not on the list of the C Series modules that have internal channels:

  http://zone.NI.com/reference/en-XX/help/370466W-01/mxdevconsid/9211interchan/#GUID-E13ADE46-5CB8-491...

  So I guess that the module is not able to compare its output to ground. He would appear in the dropdown of the channel names if available.

  Pete

  Applications Engineer OR

• DAC (analog output through sreapder?) on Spartan 3 FPGA

  Hello world

  I searched on LabView training exercises for the 3rd Spartan Board, specifically the DAC.vi and the DAChost.vi in the exercise 8. The screws are in the solution folder, but there no real explanation for the DAC specifically in Scripture in the exercises section. I was also watching Xilinx in the Board Manual, but I can't seem to find the answer to my question.

  My goal is to be out put an analog signal that is adjustable between 0 and 3.3V as a control to another system while the rest of my code is running. Of course, the premade DAC vi can be used to put analog voltages on the DAC pins, but I wonder is - it possible to the analog output of the signal through one of the connectors spreader (while the other digital connectors are also output)? It seems like it should be, but I don't know how to implement. If this is not possible, then well, I guess I have a big problem

  Thank you

  The only place where the DAC would release would be the pin of the DAC.  I doubt that there is other options routing so that the PIN because you can't get an analog signal by an FPGA.

  Kind regards

  Matt M.

• analog output digital start trigger the api c

  Hi, I'm trying to start analogue output based on a digital trigger (either PFIO or a PXI line) I can make this easy in LabVIEW.  However with the C API (through the Python wrappers), the problem is when I call DAQmxBaseWriteAnalogF64, writing will always be timeout that the acquisition was not triggered.   However, I can't call it after the trigger occurs, because obviously, it will be too late.

  I can't find any examples of C API where the analog output is triggered a digital triggering.  I can find for the analog input, but is fundamentally different that you can CONV read anytime after the trigger occurs.

  Python code as follows (functions are equivalent ot C API, even if you have no need of ot pass the task handle such that it maintained as part of the Task object)

  # create analog output task
  analog_output = Task()
  analog_output.CreateAOVoltageChan("Dev1/ao0","",-10.0,10.0, DAQmx_Val_Volts, None)
  analog_output.CfgSampClkTiming("",outputRate, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps, numSamples)
  analog_output.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
  analog_output.StartTask()
  analog_output.WriteAnalogF64(numSampsPerChan=numSamples, autoStart=False,timeout=1.0, dataLayout=DAQmx_Val_GroupByChannel, writeArray=data, reserved=None, sampsPerChanWritten=byref(samplesWritten))print("Analog output: Wrote %d samples" % samplesWritten.value)# create digital trigger dig_out = Task()dig_out.CreateDOChan("Dev1/port0", "", DAQmx_Val_ChanForAllLines)
  
  # create digital trigger function
  highSamples = 1000
  numpts = 3 * highSamples
  doData = np.zeros((numpts,), dtype=np.uint32)
  doData[highSamples:2*highSamples] =  2**32 - 1
  
  # send digital trigger
  doSamplesWritten = c_int32()
  dig_out.WriteDigitalU32(numSampsPerChan=numpts, autoStart=True, timeout=1.0, dataLayout=DAQmx_Val_GroupByChannel, writeArray=doData, reserved=None, sampsPerChanWritten=byref(doSamplesWritten))
  print("Digital output: Wrote %d samples" % doSamplesWritten.value)
  

  Hi PatrickR,

  You can review examples of code NI-DAQmx (ANSI C) text based on the production of an output using a trigger to start digital analog. If you included/checked support textual dusing your NI DAQmx driver installation, you can navigate to Windows start > all programs > National Instruments > NI DAQ > Teaxt-Based Code support > ANSI C examples > analog output > generate voltage > Mult Volt updates-Int Clk - Dig start. If you have questions/doubts about the material.

• Bipolar analog output timed sample clock Glitch on zero

  With the help of a card PCI-6221, calling in the DAQmx 8.6 with a stand-alone C application DLL.

  I create and fill a buffer as follows:

  volts1 float64 [2048];

  for (int x = 0; x)< 2048;="" x++)="">

  volts1 [x] = (-0.320) + (x * (0.640 / 2048));

  }

  My task is created and began as follows:

  TaskHandle t;

  DAQmxCreateTask ("WaveTask", &t);)

  DAQmxCreateAOVoltageChan (t, "PCI-6221/ao0", NULL,-5, 5, DAQmx_Val_Volts, NULL);

  DAQmxCfgSampClkTiming (t, NULL, 30000, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps, 2048);

  DAQmxWriteAnalogF64 (t, 2048, false,-1, DAQmx_Val_GroupByScanNumber, volts1, NULL, NULL);

  DAQmxStartTask (t);

  DAQmxWaitUntilTaskDone (t,-1);

  DAQmxStopTask (t);

  DAQmxClearTask (t);

  The foregoing, less creating and by disabling the task runs in an infinite loop.  It generates a very good approximation of a rising wave of saw (see complete.png).

  Unfortunately, when you zoom in on the time axis, a glitch becomes apparent to the point where the wave crosses zero (see glitch.png).  The glitch, as shown, is about 80 mV in amplitude and 2.5 U.S. (microseconds) in duration.

  It is very short, but could be the source of trouble.  Is there something that can be done programmatically to fix it, or makes it look like a hardware problem?

  Thank you very much!

  ~ Brian

  If you see the Specifications for the PCI-6221, you will see that there is a specification on page 3 of the energy of glitch on the analog output of this Committee.  It is a result of the CAD on the tray and is not something that can be corrected in software.  The specification is:

  

  So what you see is under the specification, so your advice is really better than the spec run.

  Hope that clarifies,

• Using of FPGA VHDL IP and analog output

  I use a system with Labview 2014 PXI. I've got Labview FPGA to program and run the card PXI-7854R.

  I have the VHDL Code I want to use to control an analog output of the card. I use the IP integration node for this now but I also tried it making the process CLIP and still have not been successful. The problem that arises is that the IP integration node must be in a timed loop, while the analog output indicates that it cannot be put in a timed loop. Is there a way to provide an output of VHDL analog outputs of the card?

  I tried to embed a loop timed within a while loop, but it still does not work.

  I can't download the VI due to the policy of the company, but suppose I'm generating a sine wave in my VHDL code which must lead to the analog output of the card (the actual wave is company owner information but it is generated by a glance to the top of the table as a sine wave VHDL would be).

  In an attempt to work the problem I retried import CLIP of the HDL code in a new project in Labview and VI. I'm still not sure about why it did not work with each other when I tried it.

  For anyone who seeks to solve this problem:

  I basically used this tutorial for the process CLIP: http://www.ni.com/tutorial/7444/en/

  It also explains the differences between the CLAMP and the IP integration node.